How do you turn off the "Try the new Safari" notification?

In OS X Yosemite and OS X El Capitan, when starting Google Chrome or Mozilla Firefox, there is an invasive, annoying, and persistent notification, titled "Try the new Safari."

There is only two options in the notification.

Clicking on "Later" will have the same notification come back next time, and "Try now"… well, I dislike being forced to do things on my own computer.

This notification reminds me of the annoying popups coming in another famous operating system, Microsoft Windows, and this is one of the many reasons why I am not using it anymore.

Is there any way to get the notification to not show up anymore without actually trying Apple's Safari?

You can get rid of it without giving in to Apple‘s desire for you to “Try Now”. Even if you click the button, they will ask you to change your default and may still ask again at a later time. I have explained it in much greater details on my blog but the gist of it are these three commands:

defaults write com.apple.coreservices.uiagent CSUIHasSafariBeenLaunched -bool YES
defaults write com.apple.coreservices.uiagent CSUIRecommendSafariNextNotificationDate -date 2050-01-01T00:00:00Z
defaults write com.apple.coreservices.uiagent CSUILastOSVersionWhereSafariRecommendationWasMade -float 99.99

You must log out and in again for the change to apply. You should actually do it immediately to prevent the system from reverting the changes.

I also cover how to stop Safari from prompting you to become the default every few days. (epimorphic touched on this briefly.) Interesting if you need to use Safari on occasions for site-compatibility, testing, or whatever reason. (Oddly enough, I have not heard any automated browsing test suite authors complaining about this yet.)